Mapac Jet Archival portfolio sleeves are acid free will prevent your precious artworks discolouring over time. They have welded holes and double welded jet black spines for strength. They are coated with a special glare reducing finish to allow easy viewing in all lights. The sheets are non-stick and can be turned without effort like pages in a book. These Mapac sleeves lie pleasingly flat even when filled with artwork. Sleeves come with jet black inserts.